"A new study enters the debate over the safety of hydraulic fracturing: researchers report that naturally occurring paths in the rock bed in northeastern Pennsylvania allowed some contaminants to migrate into shallow drinking aquifers. They found no direct connection between the contamination and shale-gas drilling operations in the region, however."

"'The good news is there is no direct link between this finding with saline water and shell gas extraction,' said Avner Vengosh, a geochemist at Duke University and a co-author of the report, published on Monday in the Proceedings of the National Academy of Sciences. 'The bad news is that we think there are natural pathways that exist between the Marcellus formation and the shallow groundwater.'"